Keysight Technologies Inc v. Centripetal Networks LLC

1. Case Identification

• Case #: IPR2023-00448
• Patent #: 11,012,474
• Filed: January 6, 2023
• Petitioner(s): Keysight Technologies, Inc.
• Patent Owner(s): Centripetal Networks, Inc.
• Challenged Claims: 1-33

2. Patent Overview

• Title: Methods and Systems for Protecting a Secured Network
• Brief Description: The ’474 patent discloses methods and systems for protecting a computer network using packet security gateways. These gateways apply packet filtering rules from a dynamic security policy that is managed by an external security policy management server, which can automatically create or alter the rules based on malicious traffic information received from a plurality of third-party threat intelligence services.

3. Grounds for Unpatentability

Ground 1: Obviousness over Law and Golnabi - Claims 1-3, 5-7, 9-11, 13-15, 17-19, 21-23, 25-27, 29-31, 33 are obvious over Law in view of Golnabi.

• Prior Art Relied Upon: Law (Application # 2011/0072506) and Golnabi (a 2006 IEEE publication, "Analysis of Firewall Policy Rules Using Data Mining Techniques").
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Law discloses the core elements of the independent claims. Law teaches a Unified Threat Management System (UTMS) where firewalls (packet security gateways) protect a network by applying rulesets (dynamic security policies). These rulesets are created and distributed by an external cyber security risk management firm (security policy management server) that aggregates threat data from a plurality of third-party sources (malicious host tracker services) to automatically construct and update the rules. The primary distinction addressed by Golnabi is the claim limitation requiring that rules be added, removed, or altered based on a "correlation" of the received malicious traffic information.
  • Motivation to Combine (for §103 grounds): Petitioner asserted that Law’s disclosure of receiving threat data from numerous independent sources would have made it obvious to a person of ordinary skill in the art (POSITA) that duplicate or overlapping information would be received. A POSITA would combine Law with Golnabi’s teachings on optimizing firewall rulesets—which explicitly include merging similar rules to eliminate redundancy—to improve the performance and efficiency of Law’s system by avoiding the processing of duplicative rules.
  • Expectation of Success (for §103 grounds): A POSITA would have had a high expectation of success, as combining the references involved applying a known rule optimization technique (Golnabi) to a known type of firewall system (Law) to achieve the predictable benefit of improved processing efficiency.

Ground 2: Obviousness over Law, Golnabi, and Wood - Claims 2, 10, 18, and 26 are obvious over Law in view of Golnabi and Wood.

• Prior Art Relied Upon: Law (Application # 2011/0072506), Golnabi (a 2006 IEEE publication), and Wood (Application # 2007/0097976).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the combination of Law and Golnabi to address dependent claims reciting that a packet matching criterion comprises a network address associated with malicious traffic. Petitioner argued that Wood discloses an adaptive system that maintains a "suspect address list" containing IP addresses of known threats (e.g., hackers, phishers) and receives a "feed of suspect addresses" from external sources to configure a router to block traffic from those addresses.
  • Motivation to Combine (for §103 grounds): A POSITA would combine Wood with the Law/Golnabi system to enhance threat protection. Petitioner contended it would have been an obvious design choice to use Wood’s feed of suspect IP addresses as an additional third-party threat data source for Law’s security management server, thereby providing more comprehensive rule generation.

Ground 3: Obviousness over Law, Golnabi, and Ke - Claims 4, 12, 20, and 28 are obvious over Law in view of Golnabi and Ke.

• Prior Art Relied Upon: Law (Application # 2011/0072506), Golnabi (a 2006 IEEE publication), and Ke (Patent 7,095,716).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground addressed dependent claims reciting the use of first and second forwarding queues where the first has a higher forwarding rate. Petitioner asserted that Ke teaches an internet security device with a priority queuing logic unit that queues certain packets (e.g., session control packets) in a priority queue to ensure quality of service and high throughput over normal packets.
  • Motivation to Combine (for §103 grounds): Because Law’s system is described as applicable to industrial process control networks, a POSITA would have appreciated that traffic on such a network would have vastly different priority levels (e.g., critical sensor data vs. routine traffic). A POSITA would combine Ke’s priority queuing with the Law/Golnabi system to prevent network bottlenecks from disrupting critical communications, a predictable and highly desirable outcome.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including that claims 5, 13, 21, and 29 are obvious over the primary combination further in view of Jungck (Application # 2009/0262741) for its teachings on network-layer transparent packet filtering, and that claims 7-8, 15-16, 23-24, and 31-32 are obvious over the primary combination further in view of Johnson (Application # 2004/0123220) for its teachings on generating and logging packet digests.

4. Key Claim Construction Positions

• Petitioner requested that the Board adopt claim constructions from prior IPR proceedings involving related patents that share the same or a substantially similar specification as the ’474 patent. Key proposed constructions included:
  • packet security gateway: "a gateway computer configured to receive packets and perform a packet transformation function on the packets"
  • dynamic security policy: "any rule, message, instruction, file, data structure, or the like that specifies criteria corresponding to one or more packets and identifies a packet transformation function to be performed on packets corresponding to the specified criteria"

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not deny institution for discretionary reasons.
  • Petitioner stipulated under Sotera that if the inter partes review (IPR) is instituted, it will not pursue in the parallel district court litigation any ground that was raised or reasonably could have been raised in the petition.
  • Petitioner argued denial under 35 U.S.C. §325(d) is inappropriate because the primary prior art reference, Law, was not considered by the examiner during prosecution of the ’474 patent, nor was it at issue in prior IPRs of related patents. Therefore, the art and arguments presented are not the same or substantially the same as those previously presented to the Office.

6. Relief Requested

• Petitioner requests institution of an IPR and cancellation of claims 1-33 of the ’474 patent as unpatentable.